The prolific use of synthetic chemicals, antibiotics, pesticides, and herbicides is of increasing concern to environmentalists, health care professionals, and the public at large as the scientific community gains a better understanding of the implications that these substances have for medicine, agriculture, and global society in general. Antibiotics and medicines are widely used for therapeutic purposes in treatments of a vast array of afflictions and infestations; chemicals and radiation are widely used on both humans and crops; insecticides are even used on children to kill head lice. While these treatments are useful and effective, there is increasing concern over the threats, both potential and actual, that the chemicals pose to the environment and to long-term human health.
A further concern in the use of chemical agents is the ability of the microbes, pathogens, bacteria and pests that are the targets of these agents to develop resistance to them. Agriculturists and physicians now believe that the typical chemical agent will have a life span of only five to ten years from its introduction before the target organism develops enough resistance to render the agent ineffective. Many of the most effective pesticides and herbicides are expected to lose their approval rating under the Food Protection Act and the Clean Air Act. These losses of effectiveness and approval rating have generated a sense of urgency among agriculturists around the world in their search for ways to remain competitive and to maintain their market share on an international basis.